All right. I knew we would end up providing Joel a plethora of advice about styles and details from our own experiences.
I wanted to give generic sound advice without personal bias, but since everyone else has, I will too!
Joel:
Despite the fancy pictures and famous names of people currently on top in the "fighting arts" business and entertainment world, you are still stuck with your current physcial conditioning. You must start there or you will certainly fail as a student.
Begin strengthening your body and building stamina and endurance. Combine stretching with cardiovascular and aerobic exercise along with weightlifting. Once your body is conditioned and strong, you will obtain much more benefit from any combination of styles mentioned in this thread.
Someone mentioned "Filipino Escrima" which is awesome. When I was 18 and a young Marine stationed in CA, my 16 year-old girlfriend was studying at Mr "I's" school. When I visited the school, I could not believe Mr "I" was the actual Dan Inosanto. While I only shook his hand once and obtained an autographed picture, I do remember the vivid demonstrations of street fighting, stick fighting and knife fighting.
Another great resource is the "Jeet Kune Do" concept school. The JKD concept schools are in many cities. They mix JKD (Bruce Lee's personal invention called Way of the Intercepting Fist) with Jiu-Jitsu and Escrima and Thai Boxing. That may be a good all-around mixture.
While boxing does not help in a crowd, it is a good training tool. One of the many reasons women FAIL at self-defense is because many have never been PUNCHED full force in the face. The shock of a facial blow, along with the natural reaction of tears and distraction with dismay, provide enough timing for an attacker to launch a second perhaps third assault.
Wrestling ability is also important. Someone mentioned most fights wind up on the ground. I have seen that to be true in my life. It is important to have the ability and strength to grasp, grapple, hold, lock, and even break an opponent's limb. Aikido, Hapkido; Gojy Ryu; especially Jiu Jitsu provide excellent training in this area.
Don't forget Nathan's advice about firearms. A fellow Marine I served with runs a firearms training school in CA:
Here is the link: http://www.tftt.com/ (Max and I served together in Bravo Company 1st Force Recon Camp Pendleton, CA in the early 80's)
You really need determine your goals, what resources you can use and how much you want this to affect your daily routine in life. It's serious. It still is for me.